Voltage-regulatihg system



R. E. CULLINGS.

VOLTAGE REGULATINQ SYSTEM. APPLICATION FILED Aue.10. 1918.

1,312,165. 1 Patented Aug. 5,1919.

WITNESSES: INVENTOR 6d. Mam Rom/m (0mm I ATTORNEY UNITED STATES PATENT oFFIoE.

ROSW'EIIL E. CULLINGS, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR T0 WEST- INGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

VDLTAGE-REGULATING SYSTEM.

Specification of Letters Patent.

Patented Aug. 5, 1919.

Applicationfilod August 10, 1918. Serial No. 249,354.

To all whom it may concern:

Be it known that I, RoswELL E. CULLINGS, a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Voltage- Regulating Systems, of which the following is a specification.

My invention relates to voltage-regulating systems and particularly to systems for governing the voltage of supply circuits by controlling the excitation of the generators which are connected to such circuits.

One object of my invention is to provide a regulator that shall respond quickly to any change of voltage in the supply circuit and maintain the voltage of such circuit substantially constant without encountering the contact troubles which are frequently experienced in connection with regulators of this type.

More specifically, my invention embodies a regulator having a main-contact relay connected across a supply circuit to be regulated. Aditferential relay, which is controlled by the main-contact relay, governs the excitation of the generator which is connected to the supply circuit and is provided with means for rendering the relay quick acting and for preventing relay-contact trouble.

In order to render the differential relay quickly responsive to voltage changes in the supply circuit, resistors are severally placed in series with the differential windings but the circuits including such devices tend to produce excessive arcing and welding of .the main-relay contact members and thus prevent satisfactor operation of the regulator.

However, satis' actory operation of the relay may be secured by connecting a condenser across the difi'erential windings of the relay so as to effect a shunt circuit through said resistors across the main-relay contact members. Thus, the differential relay is rendered quick actingby means of resistors which are inserted in series with the differential wind ings, and the main-contact troubles, which ing conductors 5 and 6. A resistor 7 is con nected in series with the shunt winding 4 and is adapted to be shunted by a regulator to be hereinafter described.

A main-contact relay 8 comprises an energizing winding 9, which is connected, through a resistor 10, across the supply conductors 5 and 6, and an armature 11 which is pivotally supported by a pivotally mounted arm 12. A contact terminal 21 is mounted on the arm 12 and is adapted to engagea stationary contact terminal :29 when the arm 12 is retracted by means of a spring 22.

A differential relay 13, c0mprisin'g windings 14 and 15, an armature 16 and a pivotally mounted arm 16, from which the armature is pivotally suspended, is controlled by the'main-contact relay 8. The winding 14 of the differential relay 13 is connected across the supply conductors 5 and 6 through resistors 17 and 18, and the differential winding 15 is adapted to be connected, through resistors 19 and 18, across the supply conductors 5 and 6 by means of the contact members 20 and 21 of the main-contact relay 8. The arm 16 of the differential relay 13 is provided with a contact terminal 23 which is adapted to engage a stationary contact terminal 24-, when retracted by means of a spring 25, for completing a short, circuit across the resistor '7 which is normally included in the circuit of the shunt field winding 1-. Adjacent terminals of the two windings 1A and 15 are connected together, and a condenser 26 is connected across the opposite terminals of the windings. A condenser 27 is connected across the contact members 23 and 24 in order to improve their operation.

Assuming the elements of the system to be in the positions illustrated in Fig; 1 and did'erential winding 14- to be energized. so as to st r the armature 16 and separate embers and 24, then the system w Upon a del of the relay 18. Thus the two windings la ized and '15 are simultaneously one neutralize each other 2 traction of the arma'l; spring 25 for sho t ciicniiing the resistor 7 by means of cncac; members 23 and 24. Consequ n l the excitation of the generater 1 isincreas and the voltage of the supply doctor is raised to normal value. ie VOlifig'Q 0 he supply circuit is raised above normal no the excitation oi the Winding 9 is raised as to overcome the action of the sprimand separate the conls-set members is 520. The separation of the contact members and 20 breaks the circuit through Elie differential winding 15 of the relay 13 and permits the winding 1% to retract l armature 16 in order to open the short circuit across Jne resistor 17.

In oper systems of the above charac- "cer WlthOllL resistors similar to 17 and 19, in the circuit of the di erential windings l and 15 of the relay 13, a considerable time was noticed in the operation of the diilerential relay and, by considerable experimenting, it was noted that the time lag of the relay 13 was substantially obviated by placing equal resistors in the circuits of the two dilierential windings, equal resistors loeing required in order to balance the operation of the two windings, The resistors insorted in series with the di'fierential winding increased the speed of the relay hut occasioned considerable sticking of the relay con tact members and oiher relay conifiact troubles, and, after further experimenting with the system, it Was discovered condenser connected across the two L rial" windings would substantially the contact trouble which Was occasioned by speedingthe relay means of the resistors l7 and 19 I Modificarions the system and arrangement and locaiion oi parts may be made in the spirit and scope of my invention, and such modifications are intended to he covered the appended claims.

I claim as my invention In a voltage regulator, a relay having differential windings, contact members the operation of the relay,

prevent contact-terminal arcing and sin 1 g.

2. in a cor-age regulacor a elay two Winding", means coin sing e -Y L n members :ror conseanti" fiillc/aglzlng said windings and for n'iiermittently' gizing the secondwinding and a coneenser connected across the windings to prevent contacazerminal sticking d arcing.

l a voltage regulator, a relay having two dill" ii'ential windings, means comprising y energizing members for const all said windings for selectively ding in accordone or energizing the second W1 'ance with the voltage obtaining; in a supply circuit, and a condenser for connecting the two in closed circuit i0 prevent e CGlleiECll terminals A geregulaton a relay having 1a! windings, resistors severally .ed in series with said windings for increasing rho speed of the relay, and a condenser forconnecting one two windings in a closed circuit to prevent relay contact or 1 eronole.

accordance with the voltage in he supply circuit, a difierential relay condenser connected across the windings of. the J oren'tial relay, and means controlled by differential relay for governing the vcriage of the supply circuit.

in a voltage regulator for a supply circuit, a rnain-contact relay operated in accordance with the voltage obtaining in the supply circnil), a relay having 'difierential ad gs and controlled by the main-contact relay, resistors severally connected in series the differential windings for increasing ed of the relay, a condenser i'or es- A 111;; a closed circuit through. the difential windings to prevent relay-contact rroulole, and means controlled by the differential relay for governing the voltage of the circuit. sestiniony whereof, I have -'liereunto crihed my this 31st day 0;: July E. cone:

broiled by she main-contact relay, a con- 

